1. Field of the Invention
This invention relates to electro-hydraulic pressure regulating valves.
2. Description of the Prior Art
Electro-hydraulic pressure regulating valves typically include a supply pressure port, a control pressure port, and an exhaust port. An electric solenoid moves a valve member or armature plate between seated positions on the supply pressure and exhaust ports to expose the control pressure port alternately to a supply pressure and to an exhaust whereby a control pressure is regulated at the control pressure port. Fluid flow through and the pressure capacity of the valve depend, at least in part, on the lift of the valve member relative to the supply pressure port and the exhaust port and the solenoid electro-magnetic force (EMF) of the valve. An electro-hydraulic pressure regulating valve according to this invention incorporates a novel combination of structural elements which contribute to optimizing the pressure and flow capacity of the valve while minimizing the required solenoid EMF.